U.S. patent application number 17/265702 was filed with the patent office on 2021-08-05 for user equipment and base station device.
This patent application is currently assigned to NTT DOCOMO, INC.. The applicant listed for this patent is NTT DOCOMO, INC.. Invention is credited to Xiaolin Hou, Ryosuke Osawa, Huan Wang, Xufei Zheng.
Application Number | 20210243586 17/265702 |
Document ID | / |
Family ID | 1000005581095 |
Filed Date | 2021-08-05 |
United States Patent
Application |
20210243586 |
Kind Code |
A1 |
Osawa; Ryosuke ; et
al. |
August 5, 2021 |
USER EQUIPMENT AND BASE STATION DEVICE
Abstract
A user equipment includes a receiving unit that executes sensing
for a part of candidate resources to be used for transmission of
inter-terminal direct communication, a control unit that determines
a resource to be used for transmission based on a result of the
sensing, and a transmitting unit that transmits a message to
another units of user equipment using the determined resource.
Inventors: |
Osawa; Ryosuke; (Chiyoda-ku,
Tokyo, JP) ; Wang; Huan; (Beijing, Haidian District,
CN) ; Zheng; Xufei; (Beijing, Haidian District,
CN) ; Hou; Xiaolin; (Beijing, Haidian District,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NTT DOCOMO, INC. |
Tokyo |
|
JP |
|
|
Assignee: |
NTT DOCOMO, INC.
Tokyo
JP
|
Family ID: |
1000005581095 |
Appl. No.: |
17/265702 |
Filed: |
September 13, 2018 |
PCT Filed: |
September 13, 2018 |
PCT NO: |
PCT/JP2018/034082 |
371 Date: |
February 3, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04W 8/005 20130101;
H04W 72/0446 20130101; H04W 72/12 20130101; H04W 4/40 20180201;
H04W 92/18 20130101; H04W 74/0816 20130101 |
International
Class: |
H04W 8/00 20060101
H04W008/00; H04W 72/12 20060101 H04W072/12; H04W 72/04 20060101
H04W072/04; H04W 74/08 20060101 H04W074/08 |
Claims
1. A user equipment, comprising: a receiving unit that executes
sensing for a part of candidate resources to be used for
transmission of inter-terminal direct communication; a control unit
that determines a resource to be used for transmission based on a
result of the sensing; and a transmitting unit that transmits a
message to another user equipment using the determined
resource.
2. The user equipment according to claim 1, wherein the part of the
candidate resources to be used for the transmission is one symbol
at a beginning in a time domain of the candidate resources to be
used for the transmission or a plurality of symbols allocated from
a second symbol from the beginning.
3. The user equipment according to claim 2, wherein, upon detecting
that a resource is used in the one symbol at the beginning in the
time domain of the candidate resource to be used for the
transmission, the plurality of symbols allocated from the second
symbol from the beginning are not sensed.
4. The user equipment according to claim 2, wherein, upon not
detecting that a resource is used in the one symbol at the
beginning in the time domain of the candidate resource to be used
for the transmission, the plurality of symbols allocated from the
second symbol from the beginning are sensed.
5. The user equipment according to claim 1, wherein, upon detecting
a notification indicating that the candidate resources to be used
for the transmission are scheduled, the candidate resources to be
used for the transmission are not sensed and are excluded from
resource candidates used for transmission.
6. A base station device, comprising: a receiving unit that
receives information indicating that a candidate resource used for
transmission of inter-terminal direct communication is reserved by
a first user equipment; and a control unit that prevents scheduling
the candidate resources to be used for the transmission to a user
equipment based on the information indicating the reservation,
wherein, when the candidate resource to be used for the
transmission is already scheduled to a second user equipment,
scheduling a new resource to the first user equipment is executed.
Description
TECHNICAL FIELD
[0001] The present invention relates to a user equipment and a base
station device in a wireless communication system.
BACKGROUND ART
[0002] In Long Term Evolution (LTE), successor systems of LTE (for
example, LTE-Advanced (LTE-A), and New Radio (NR) (also called
5G)), device to device (D2D) technology in which units of user
equipment perform communication directly with each other without
going through a base station device is under review (for example,
Non-Patent Document 1).
[0003] In D2D, it is possible to reduce traffic between a user
equipment and a base station device, and communication between
units of user equipment can be performed even when a base station
device is unable to perform communication in the event of a
disaster or the like. In 3rd Generation Partnership Project (3GPP),
D2D is called "sidelink," but D2D which is a more general term is
used in this specification. However, in the description of an
embodiment to be described later, a sidelink is also used if
necessary.
[0004] D2D communication is roughly classified into D2D discovery
for discovering other equipments which are capable of performing
communication and D2D communication (also referred to as D2D direct
communication, D2D communication, or inter-terminal direct
communication) in which direct communication between units of user
equipment is performed. Hereinafter, when D2D communication, D2D
discovery, and the like are not particularly distinguished, they
are referred to simply as D2D. A signal transmitted and received by
D2D is referred to as a D2D signal. In NR, various use cases of
services related to vehicle to everything (V2X) are under review
(for example, Non-Patent Document 2).
RELATED ART DOCUMENT
Non-Patent Document
[0005] Non-Patent Document 1: 3GPP TS 36.211 V15.2.0 (2018-06)
[0006] Non-Patent Document 2: 3GPP TR 22.886 V15.1.0 (2017-03)
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0007] When a case in which a resource to be used for D2D
communication is scheduled to a user equipment by a base station
device or the like and a case in which a user equipment
autonomously selects a resource to be used for D2D communication
coexist, influence of collision of resources is assumed to
increase.
[0008] The present invention has been accomplished in view of the
foregoing, and an object is to reduce collision of resources to be
used by a user equipment in inter-terminal direct
communication.
Means for Solving the Problem
[0009] According to the technology of the disclosure, provided is a
user equipment including a receiving unit that executes sensing for
a part of candidate resources to be used for transmission of
inter-terminal direct communication, a control unit that determines
a resource to be used for transmission based on a result of the
sensing, and a transmitting unit that transmits a message to
another user equipment using the determined resource.
Advantage of the Invention
[0010] According to the technology of the disclosure, it is
possible to reduce collision of resources to be used by a user
equipment in inter-terminal direct communication.
BRIEF DESCRIPTION OF DRAWINGS
[0011] FIG. 1 is a diagram for illustrating V2X;
[0012] FIG. 2 is a diagram for illustrating an example (1) of a
wireless communication system;
[0013] FIG. 3 is a diagram for illustrating an example (2) of a
wireless communication system;
[0014] FIG. 4 is a diagram for illustrating an example (1) of an
operation of a user equipment in an embodiment of the present
invention;
[0015] FIG. 5 is a diagram for illustrating an example (2) of an
operation of the user equipment in an embodiment of the present
invention;
[0016] FIG. 6 is a diagram illustrating an example (1) of sensing
in an embodiment of the present invention;
[0017] FIG. 7 is a diagram illustrating an example (1) of resource
arrangement in an embodiment of the present invention;
[0018] FIG. 8 is a diagram illustrating an example (2) of sensing
in an embodiment of the present invention;
[0019] FIG. 9 is a diagram illustrating an example (2) of a
resource arrangement in an embodiment of the present invention;
[0020] FIG. 10 is a diagram for illustrating an example (1) of an
operation related to resource exclusion in an embodiment of the
present invention;
[0021] FIG. 11 is a diagram illustrating an example of a
notification related to a resource to be scheduled in an embodiment
of the present invention;
[0022] FIG. 12 is a diagram for illustrating an example (2) of an
operation related to resource exclusion in an embodiment of the
present invention;
[0023] FIG. 13 is a diagram illustrating an example of a
notification related to a resource to be reserved in an embodiment
of the present invention;
[0024] FIG. 14 is a diagram for illustrating an example of an
operation related to scheduling in an embodiment of the present
invention;
[0025] FIG. 15 is a diagram for illustrating an example of an
operation related to MAC selection in an embodiment of the present
invention;
[0026] FIG. 16 is a diagram illustrating an example of a functional
configuration of a base station device 10 in an embodiment of the
present invention;
[0027] FIG. 17 is a diagram illustrating an example of a functional
configuration of a user equipment 20 in an embodiment of the
present invention; and
[0028] FIG. 18 is a diagram illustrating an example of a hardware
configuration of a base station device 10 or a user equipment 20 in
an embodiment of the present invention.
EMBODIMENTS OF THE INVENTION
[0029] Hereinafter, an embodiment of the present invention will be
described with reference to the appended drawings. Note that the
following is an example, and embodiments to which the present
invention is applied are not limited to the following
embodiment.
[0030] In an operation of a wireless communication system of an
embodiment of the present invention, existing technology is
appropriately used. Here, the existing technology is, for example,
existing LTE but not limited to existing LTE. Further, the term
"LTE" used in this specification shall have a broad meaning
including LTE-Advanced and a scheme subsequent to LTE-Advanced (for
example, NR), or a wireless local area network (LAN) unless
otherwise configured forth herein.
[0031] In an embodiment of the present invention, a duplex scheme
may be a time division duplex (TDD) scheme, a frequency division
duplex (FDD) scheme, or any other scheme (for example, a flexible
duplex or the like).
[0032] In the following description, a method of transmitting a
signal using a transmission beam may be digital beam forming of
transmitting a signal (pre-coded with a pre-coding vector)
multiplied by a pre-coding vector or may be analog beam forming for
realizing beam forming using a variable phase shifter in a radio
frequency (RF) circuit. Similarly, a method of receiving a signal
using a reception beam may be digital beam forming of multiplying a
received signal by a predetermined weight vector or may be analog
beam forming of realizing beam forming using a variable phase
shifter in a RF circuit. Hybrid beam forming in which digital beam
forming and analog beam forming are combined may be applied to
transmission and reception. Further, transmitting a signal using a
transmission beam may be transmitting a signal through a specific
antenna port. Similarly, receiving a signal using a reception beam
may be receiving a signal through a particular antenna port. An
"antenna port" refers to a logical antenna port or a physical
antenna port defined in the 3GPP standard. In addition, a precoding
or the beam forming is also referred to as a "pre-coder" or a
"spatial domain filter."
[0033] A method of forming the transmission beam and the reception
beam is not limited to the above method. For example, in the base
station device 10 and the user equipment 20 having a plurality of
antennas included in the wireless communication system of an
embodiment of the present invention, a method of changing an angle
of each antenna may be used, a method in which a method using a
precoding vector and a method of changing an angle of an antenna
are combined may be used, a method of switching and using different
antenna panels may be used, a method of using a combination of a
plurality of antenna panels may be used, or any other method may be
used. Further, for example, a plurality of different transmission
beams may be used in a high frequency band. Using a plurality of
transmission beams is referred to as a multi-beam operation, and
using a single transmission beam is used is referred to as a single
beam operation.
[0034] Further, in an embodiment of the present invention, when a
wireless parameter or the like is configured, it may mean that a
predetermined value is "pre-configured" or it may mean that a
wireless parameter notified from the base station device 10 or the
user equipment 20 is configured.
[0035] FIG. 1 is a diagram for illustrating V2X. In 3GPP,
implementing vehicle to everything (V2X) or enhanced V2X (eV2X) by
extending a D2D function is under review, and specifications
thereof are in progress. As illustrated in FIG. 1, V2X is a part of
intelligent transport systems (ITS) and is a generic term of
vehicle to vehicle (V2V) meaning a communication form performed
between automobiles, vehicle to infrastructure (V2I) meaning a
communication form performed between an automobile and a road-side
unit (RSU) installed on a road side, vehicle to nomadic device
(V2N) meaning a communication mode performed between an automobile
and a mobile terminal carried by a driver, and vehicle to
pedestrian (V2P) meaning a communication mode performed between an
automobile and a mobile terminal carried by a pedestrian.
[0036] In 3GPP, V2X using cellular communication and inter-terminal
communication of LTE or NR is being studied. For V2X of LTE or NR,
review not limited to 3GPP specification is expected to be
conducted from now. For example, cost reduction by securing of
interoperability and implementing of an upper layer, a combining or
switching method of a plurality of radio access technologies
(RATs), regulation response in each country, and data acquisition,
delivery, database management, and use method of V2X platform of
LTE or NR are expected to be under review.
[0037] In an embodiment of the present invention, a form in which
the communication device is installed on a vehicle is mainly
assumed, but the embodiment of the present invention is not limited
to this form. For example, the communication device may be a
terminal carried by a person, the communication device may be a
device installed in a drone or an aircraft, and the communication
device may be a base station, an RSU, a relay station (relay node),
a user equipment having a scheduling capability, or the like.
[0038] Note that sidelink (SL) may be distinguished from uplink
(UL) or downlink (DL) based on one of the following 1) to 4) or a
combination thereof. Further, SL may have any other name. [0039] 1)
A resource arrangement in a time domain [0040] 2) A resource
arrangement in a frequency domain [0041] 3) A synchronization
signal to be referred to (including a sidelink synchronization
signal (SLSS)) [0042] 4) A reference signal used for path loss
measurement for transmission power control
[0043] Further, for orthogonal frequency division multiplexing
(OFDM) of SL or UL, any one of cyclic-prefix OFDM (CP-OFDM),
discrete Fourier transform-spread-OFDM (DFT-S-OFDM), non-transform
pre-coded OFDM, and transform pre-coded OFDM may be applied.
[0044] In SL of LTE, Mode 3and Mode 4 are specified for SL resource
allocation to the user equipment 20. In Mode 3, transmission
resources are dynamically allocated in accordance with downlink
control information (DCI) transmitted from the base station device
10 to the user equipment 20. In Mode 3, semi persistent scheduling
(SPS) can be performed as well. In Mode 4, the user equipment 20
autonomously selects transmission resources from a resource
pool.
[0045] A slot in an embodiment of the present invention may be
replaced with a mini slot, a sub frame, a radio frame, a
transmission time interval (TTI), or the like.
[0046] Generally, there are three types of media access control
(MAC) configurations of an ad hoc network such as V2X: distributed;
semi-distributed; and centralized. In the centralized MAC, the base
station device 10 performs a resource allocation as a
coordinator/manager. For example, the LTE Sidelink transmission
mode 3 or the like correspond to the centralized MAC. For example,
a disadvantage of the centralized MAC lies in that it is unable to
be operated outside the coverage. Further, the base station device
10 is affected when an overhead associated with a scheduling
request (SR) and a buffer status report (BSR) becomes excessive.
For example, when a large number of UE-equipped vehicles transmit
the SR and the BSR, since a large overhead is predicted, it is
necessary for a network to support a low delay SR procedure.
[0047] FIG. 2 is a diagram for illustrating an example (1) of a
wireless communication system. A wireless communication system
illustrated in FIG. 2 is a configuration example of a
semi-distributed MAC, and a group is constituted at least by one
user equipment 20 which is a header and one or more units of user
equipment 20 which are members. In the example of FIG. 2, there is
a UE group including four units of user equipment 20, that is, a
user equipment 20A which is a header and a user equipment 20B, a
user equipment 20C, and a user equipment 20D which are members. In
the semi-distributed MAC, the user equipment 20A performs a
resource allocation or scheduling as a coordinator/manager. In the
semi-distributed MAC, a plurality of units of user equipment 20 are
divided into UE groups each including one or more units of user
equipment 20, and the user equipment 20 which is the header of the
UE group executes an SL resource allocation or scheduling for the
user equipment 20 which is a member. The scheduling of the
semi-distributed MAC can solve the above-described disadvantages of
the distributed MAC or the centralized MAC. The header refers to a
user equipment 20 that allocates or schedules a resource to be used
for the inter-terminal direct communication to other units of user
equipment 20 within a resource set associated with the UE group in
the UE group including a plurality of units of user equipment 20.
The member refers to a user equipment 20 to which the resource to
be used for the inter-terminal direct communication is allocated or
scheduled from the user equipment 20 which is the header in the UE
group including a plurality of units of user equipment 20.
[0048] FIG. 3 is a diagram for illustrating an example (2) of a
wireless communication system. The wireless communication system
illustrated in FIG. 3 is a configuration example of the distributed
MAC, and a group is configured by one or more units of user
equipment 20 which are members. In the example of FIG. 2, there is
a UE group including four units of user equipment 20, that is, a
user equipment 20A, a user equipment 20B, a user equipment 20C, and
a user equipment 20D. In the distributed MAC, there is no
coordinator/manager that performs the resource allocation or
scheduling. The user equipment 20 autonomously selects the SL
resource which its own device uses for transmission. For example,
802.11p, the LTE Sidelink transmission mode 4 or the like
correspond to distributed MAC. The disadvantages of the distributed
MAC are as follows. In the mode 4, periodic traffic is assumed, and
it is not suitable for aperiodic traffic. In 802.11p using carrier
sense multiple access (CSMA), contention of resources frequently
occurs, and requirements of high reliability are unable to be
satisfied in a situation in which the number of terminals is
large.
[0049] FIG. 4 is a diagram for illustrating an example (1) of an
operation of the user equipment in an embodiment of the present
invention. A scheduling type MAC such as the centralized MAC or the
semi-distributed MAC and an autonomous resource selection type MAC
such as the distributed MAC can complement each other by taking
each other's advantages. On the other hand, since different
resource selection mechanisms are used, it is necessary to reduce a
resource collision that occurs between the units of user equipment
20 using their respective MAC mechanisms. Further, it is necessary
to properly specify conditions for determining a MAC mechanism to
be used. Further, in the scheduling type MAC, the base station
device 10 may perform scheduling, or the user equipment 20 may
perform scheduling. Further, in the autonomous resource selection
type MAC, the resource selection may be executed by any
sensing.
[0050] In FIG. 4, the UE group includes a user equipment 20A which
is a header and a user equipment 20B, a user equipment 20C, and a
user equipment 20D which are members, and a user equipment 20E that
does not belong to the UE group to which the user equipment 20A and
the like belong. Therefore, the user equipment 20E executes the
autonomous resource selection. Here, since the user equipment 20
belonging to the UE group uses resources based on scheduling, both
the scheduling type MAC and the autonomous resource selection type
MAC are used in parallel. Therefore, it is necessary to reduce the
resource collision or to select the MAC mechanism.
[0051] FIG. 5 is a diagram for illustrating an example (2) of an
operation of the user equipment in an embodiment of the present
invention. In FIG. 5, the UE group includes a user equipment 20A
which is a header and a user equipment 20B, a user equipment 20C,
and a user equipment 20D which are members. Here, although the user
equipment 20B belongs to the UE group, the user equipment 20B is
unable to receive scheduling or resource allocation from the user
equipment 20A since resources are insufficient. Therefore, the user
equipment 20B executes the autonomous resource selection. Since the
user equipment 20A, the user equipment 20B, or the user equipment
20C uses resources based on scheduling, both the scheduling type
MAC and the autonomous resource selection type MAC are used in
parallel. Therefore, it is necessary to reduce the resource
collision or to select the MAC mechanism.
[0052] In this regard, when the MAC mechanisms of performing
different resource selection methods are used between the user
equipment 20, the resource collision can be reduced by the
following method 1) or 2).
[0053] 1) It is predefined whether resource pools orthogonal to
each other are configured for the user equipment 20 operating with
the scheduling type MAC and the user equipment 20 operating with
the autonomous resource selection type MAC, respectively. In other
words, it is specified in advance whether or not one MAC mechanism
is configured for each resource pool. PHY layer signaling or upper
layer signaling is used to notify of the configuration of the
resource pool. For example, downlink control information (DCI),
sidelink control information (SCI), a MAC control element (MAC-CE),
a MAC header, or radio resource control (RRC) signaling may be
used. Further, cell specific signaling, UE group common signaling,
UE group specific signaling, UE common signaling, and/or UE
specific signaling may be used to notify of the configuration of
the resource pool.
[0054] 2) It is specified in advance whether or not a resource pool
shared by the user equipment 20 operating with the scheduling type
MAC and the user equipment 20 operating with the autonomous
resource selection type MAC is configured. PHY layer signaling or
upper layer signaling is used to notify of the configuration of the
resource pool. For example, the DCI, the SCI, the MAC-CE, the MAC
header, or the RRC signaling may be used. Further, cell specific
signaling, UE group common signaling, UE group specific signaling,
UE common signaling, and/or UE specific signaling may be used to
notify of the configuration of the resource pool. The user
equipment 20 executes the autonomous resource selection while
avoiding a collision with the resource allocated based on
scheduling.
[0055] FIG. 6 is a diagram illustrating an example (1) of sensing
in an embodiment of the present invention. The resource pool
configured or predefined as described in 2) above is designed to
have a specific structure for allowing the user equipment 20 to
perform autonomous resource selection for detecting whether a
resource is occupied or a resource is scheduled.
[0056] A sensing unit is configured or specified in advance in a
resource unit. The sensing unit is a unit of a period in which
sensing is executed and may be, for example, one or more symbols. A
symbol constituting the sensing unit is referred to as a sensing
symbol. The resource unit is a unit in which a resource is
allocated, and a resource set may be constituted by a plurality of
resource units. For example, the sensing unit is configured for one
scheduled resource unit included in the resource set. A length of
the resource unit in the time domain may be, for example, 1 slot, 1
mini slot, 1 sub frame, or 1 TTI. One or more symbols from the
beginning of the resource unit are used as the sensing symbol which
is the sensing unit. Further, one or more symbols from the
beginning of the resource unit may be similarly used as an auto
gain control (AGC) training symbol.
[0057] FIG. 6 illustrates an example of one resource unit, in which
a length in the frequency domain is one sub channel, a length in
the time domain is one TTI, and one symbol at the head of the
resource unit is a sensing symbol identifying a resource to be
scheduled to other units of user equipment.
[0058] FIG. 7 is a diagram illustrating an example (1) of a
resource arrangement in an embodiment of the present invention. In
a case in which the user equipment 20 performs message transmission
with a resource unit scheduled to its own device, the user
equipment 20 may transmit signaling in the sensing unit to indicate
that the resource unit is scheduled. For example, as illustrated in
FIG. 7, signaling for identifying that the resource unit is
scheduled may be transmitted in a time domain before a message or
in a time domain at a start of the resource unit, while being time
division multiplexed or frequency division multiplexed with the
message transmission. The signaling for identifying that the
resource unit is scheduled may be a sensing reference signal
transmitted at the start of the transmission of the message.
Further, for example, the message is control signaling and/or data
in a physical sidelink broadcast channel (PSBCH), a physical
sidelink control channel (PSCCH), a physical sidelink shared
channel (PSSCH), or a physical sidelink discovery channel
(PSDCH).
[0059] FIG. 8 is a diagram illustrating an example (2) of sensing
in an embodiment of the present invention. A sensing unit
identifying a resource unit scheduled to another user equipment or
the like may be different from a sensing unit identifying a
resource unit selected by autonomous resource selection by other
units of user equipment or the like. The sensing unit identifying
the resource unit scheduled to other units of user equipment or the
like may be configured or specified in advance in a time domain
before the sensing unit identifying the resource unit selected by
autonomous resource selection by other units of user equipment or
the like. FIG. 8 illustrates an example in which the sensing unit
identifying the resource unit scheduled to other units of user
equipment or the like is configured in a first symbol of the
resource unit, and the sensing unit identifying the resource unit
selected by autonomous resource selection by other units of user
equipment or the like is configured in a second symbol, a third
symbol, and a fourth symbol from the beginning. The length of the
sensing unit is not limited to three symbols and may be an
arbitrary number of symbols of 1 or more.
[0060] FIG. 9 is a diagram illustrating an example (2) of a
resource arrangement in an embodiment of the present invention.
When the sensing described in FIG. 8 is executed, as illustrated in
FIG. 9, all of resources in the time domain can be used for the UE
scheduling. On the other hand, a part of the resources can be used
for the UE autonomous selection in the time domain.
[0061] FIG. 10 is a diagram for illustrating an example (1) of an
operation related to resource exclusion in an embodiment of the
present invention. The user equipment 20 that executes the
autonomous resource selection may execute sensing for the sensing
unit identifying the resource unit scheduled to other units of user
equipment or the like and the sensing unit identifying the resource
unit selected by autonomous resource selection by other units of
user equipment or the like. In a case in which the resource unit is
the resource unit scheduled to other units of user equipment or the
like or the resource unit selected by the autonomous resource
selection by other units of user equipment or the like, the user
equipment 20 excludes the resource unit from candidate resources to
be used for transmission of its own device. In a case in which a
measurement result in the sensing unit exceeds a configured or
pre-specified threshold value, the resource unit corresponding to
the sensing unit is excluded from the candidate resources used for
transmission. Examples of the measurement result include a
reference signal received power (RSRP), a received signal strength
indicator (RSSI), a reference signal received quality (RSRQ), and a
signal to interference plus noise ratio (SINR).
[0062] Further, when a resource unit scheduled to other units of
user equipment or the like is detected, the user equipment 20 need
not execute sensing in the sensing unit identifying the resource
unit selected by the autonomous resource selection. On the other
hand, when a resource unit scheduled to other units of user
equipment or the like is not detected, the user equipment 20
executes sensing in the sensing unit identifying the resource unit
selected by autonomous resource selection by other units of user
equipment or the like.
[0063] Hereinafter, the resource unit is also referred to as a
resource. In step S11, the user equipment 20 senses a symbol
included in the sensing unit identifying a resource to be
scheduled. Then, the user equipment 20 determines whether or not
the use of the resource is detected (S12). When the use of the
resource is detected (YES in S12), the process proceeds to step
S13, and when the use of the resource is not detected (NO in S12),
the process proceeds to step S14. In step S13, the user equipment
20 excludes the resource in which the use of the resource is
detected from the candidate resources used for transmission.
[0064] On the other hand, in step S14, the user equipment 20 senses
the symbol corresponding to the autonomously selected resource.
Then, the user equipment 20 determines whether or not the use of
the resource is detected (S15). When the use of the resource is
detected (YES in S15), the process proceeds to step S13, and the
resource in which the use of the resource is detected is excluded
from the candidate resources used for transmission, and when the
use of the resource is not detected (NO in S15), the flow ends.
[0065] FIG. 11 is a diagram illustrating an example of a
notification related to a scheduled resource in an embodiment of
the present invention. As illustrated in FIG. 11, in order to
prevent the user equipment 20 that executes the autonomous resource
selection from selecting the resource scheduled to other units of
user equipment or the like, a notification of the scheduled
resource may be given to the user equipment 20 that executes the
autonomous resource selection before message transmission. The
notification may be transmitted to the user equipment 20 in an x-th
symbol, an x-th slot, an x-th mini slot, an x-th sub frame or an
x-th TTI before the message transmission. As x, a fixed value is
configured or specified in advance. Further, x may be designated by
a range. For example, x may be designated by a range from x_min to
x_max.
[0066] Further, the notification of the scheduled resource may be a
notification via resource reservation. For example, when message
transmission is performed periodically, the resource reservation
including a resource to be used for subsequent message transmission
may be performed.
[0067] Further, PHY layer signaling or upper layer signaling is
used for the notification of the scheduled resource. For example,
the DCI, the SCI, the MAC-CE, the MAC header, or the RRC signaling
may be used. When the notification of the scheduled resource is
received or when it is detected that a measurement result of
sensing a resource in which the notification of the scheduled
resource is transmitted exceeds a predetermined threshold value,
the user equipment 20 excludes the notified resource from the
candidate resources used for transmission. The measurement result
is the RSRP, the RSSI, the RSRQ, the SINR, or the like.
[0068] FIG. 12 is a diagram for illustrating an example (2) of an
operation related to resource exclusion in an embodiment of the
present invention. In step S21, the user equipment 20 determines
whether there is a notification of information indicating the
scheduled resource to other unit of user equipment or the like.
When there is notification of the information indicating the
scheduled resource to other units of user equipment of the like
(YES in S21), the process proceeds to step S22, and when there is
no notification of the information indicating the resource
scheduled to other units of user equipment or the like (NO in S21),
the flow ends. In step S22, the notified resource is excluded from
the candidate resources used for transmission.
[0069] FIG. 13 is a diagram illustrating an example of a
notification related to a reserved resource in an embodiment of the
present invention. As illustrated in FIG. 13, the user equipment 20
that executes the autonomous resource selection may reserve a
resource to be used for transmission in a next period of
transmission in an autonomously selected resource. For example, the
resource reservation by periodic traffic is assumed.
[0070] PHY layer signaling or upper layer signaling is used for a
notification of information for reserving a resource used for
transmission in the next period in the autonomously selected
resource. For example, the UCI, the SCI, the MAC-CE, the MAC
header, or the RRC signaling may be used. It may be configured or
specified in advance whether or not the reservation is
permitted.
[0071] When the information for reserving the resource used for the
transmission in the next cycle of the transmission in the
autonomously selected resource is detected, the base station device
10 or the user equipment 20 executing the scheduling may avoid
scheduling the resource reserved for the other units of user
equipment 20. When the reserved resource is a resource to be
scheduled to other units of user equipment 20, a new resource may
be rescheduled to the user equipment 20 which has transmitted the
information for reserving the resource. It may be configured or
specified in advance that the rescheduled resource is given a
priority over a resource which is autonomously selected or
reserved. For example, the priority order of resources may be as
follows. A first degree of priority is given a priority over a
second degree of priority, and the second degree of priority is
given a priority over a third degree of priority. [0072] The first
degree of priority: resources scheduled by the base station device
10 [0073] The second degree of priority: resources scheduled by the
user equipment 20 [0074] The third degree of priority: resources
autonomously selected by the user equipment 20
[0075] When information for reserving the resource used for the
transmission in the next cycle of the transmission in the
autonomously selected resource that is transmitted from another
units of user equipment 20 is detected, the detecting user
equipment 20 that executes autonomous resource selection may
exclude the resource from the candidate resources used for
transmission.
[0076] FIG. 14 is a flowchart for illustrating an example of an
operation related to scheduling in an embodiment of the present
invention. In step S31, the base station device 10 or the user
equipment 20 executing the scheduling determines whether or not the
information indicating the resource reserved by the autonomous
selection is detected. When the information indicating the resource
reserved by the autonomous selection is detected (YES in S31), the
process proceeds to step S32, and when the information indicating
the resource reserved by the autonomous selection is not detected
(NO in S32), the flow ends. In step S32, the base station device 10
or the user equipment 20 executing the scheduling does not use the
notified reserved resource for scheduling.
[0077] FIG. 15 is a flowchart for illustrating an example of an
operation related to MAC selection in an embodiment of the present
invention. The user equipment 20 may determine selection of any one
of the scheduling type MAC and the autonomous resource selection
type MAC based on any one of 1) to 4) to be described below or a
combination thereof.
[0078] 1) The user equipment 20 selects the scheduling type MAC
when the user equipment 20 is the header or the member of the UE
group, and otherwise selects the autonomous resource selection type
MAC.
[0079] 2) The user equipment 20 selects the autonomous resource
selection type MAC when a scheduling command is not received until
x symbols, x slot, x mini slots, x sub frames, x TTIs, or x ms's
after the user equipment 20 transmits the SR. A value of x may be
configured or specified in advance. The details of an autonomous
resource selection operation such as random selection or sensing
execution may be configured or specified in advance, or may be
performed based on UE implementation.
[0080] 3) The user equipment 20 selects the autonomous resource
selection type MAC when a period during which the scheduling
command is not received exceeds x symbols, x slot, x mini slots, x
sub frames, x TTIs, or x ms's which are a threshold value based on
latency requirements. A value of x may be configured or specified
in advance. The details of an autonomous resource selection
operation such as random selection or sensing execution may be
configured or specified in advance, or may be performed based on UE
implementation. FIG. 15 is a flowchart for illustrating the above
operation. In step S41, it is determined whether the period during
which the scheduling command is not received exceeds the threshold
value based on latency requirements. When the threshold value is
exceeded (YES in S41), the process proceeds to step S42, and when
the threshold value is not exceeded (NO in S41), the process
proceeds to step S43. In step S42, the user equipment 20 selects
the autonomous resource selection type MAC and executes the
autonomous resource selection. In step S43, the user equipment 20
selects or continues the scheduling type MAC and uses the scheduled
resource.
[0081] 4) The base station device 10 or the user equipment 20
executing scheduling configures a MAC mechanism to be used. The
base station device 10 which is the scheduler or the user equipment
20 executing the scheduling excludes a certain user equipment 20
from the UE group. The excluded user equipment 20 selects the
autonomous resource selection type MAC. The exclusion may be
temporary, or the exclusion may continue for x times of message
transmission or for a period corresponding to x symbols/slots/mini
slots/sub frames/TTIs/ms. Further, there may be explicit
notification of cancellation of the exclusion. PHY layer signaling
or upper layer signaling is used to transmit information indicating
the exclusion, information indicating the cancellation of the
exclusion, or transmission of the value of x. For example, the DCI,
the SCI, the MAC-CE, the MAC header, or the RRC signaling may be
used. Further, the base station device 10 which is the scheduler or
the user equipment 20 which executes the scheduling may cause a
certain user equipment 20 to select the autonomous resource
selection type MAC by transmitting a control signal (for example, a
scheduling command or a resource configuration/notification)
related to scheduling or resource allocation. The control signal
may include a resource set or a resource unit used for the
autonomous resource selection. The details of an autonomous
resource selection operation such as random selection or sensing
execution may be configured or specified in advance, or may be
performed based on UE implementation. PHY layer signaling or upper
layer signaling is used for the notification of the control signal.
For example, the DCI, the SCI, the MAC-CE, the MAC header, or the
RRC signaling may be used. Further, UE specific signaling, UE
common signaling, UE group specific signaling, UE group common
signaling, and/or cell specific signaling may be used for the
notification of the control signal.
[0082] Further, a message which is SL-transmitted may be any
signaling. For example, the control signal and/or data transmitted
through any one of the PSBCH, the PSCCH, the PSSCH, or the PSDCH
may be a message. Further, the user equipment 20 may be supported
to configure one or more resource allocation mechanisms. The
resource allocation mechanism to be used may be configured or
specified in advance. Further, it may be defined as a UE capability
that the user equipment 20 can configure one or more resource
allocation mechanisms. For example, the UE capability includes
information indicating the resource allocation mechanism to be
supported.
[0083] According to the above-described embodiment, when the
scheduling type MAC such as the centralized MAC or the
semi-distributed MAC coexists with the autonomous resource
selection type MAC such as the distributed MAC, the user equipment
20 can improve the performance of the system by preventing the
collision of the SL resource.
[0084] In other words, it is possible to reduce the collision of
the resources used by the user equipment in the inter-terminal
direct communication.
Device Configuration
[0085] Next, a functional configuration example of each of the base
station device 10 and the user equipment 20 that execute the
processes and the operation described so far will be described.
Each of the base station device 10 and the user equipment 20 has
the function of implementing the embodiment. Here, each of the base
station device 10 and the user equipment 20 may have only some of
the functions in the embodiment.
Base Station Device 10
[0086] FIG. 16 is a diagram illustrating an example of a functional
configuration of the base station device 10. As illustrated in FIG.
16, the base station device 10 has a transmitting unit 110, a
receiving unit 120, a setting unit 130, and a control unit 140. The
functional configuration illustrated in FIG. 12 is merely an
example. As long as the operation according to an embodiment of the
present invention can be executed, the function classification and
the name of the function unit are not consequential.
[0087] The transmitting unit 110 has a function of generating a
signal to be transmitted to the user equipment 20 and transmitting
the signal wirelessly. The receiving unit 120 has a function of
receiving various types of signals transmitted from the user
equipment 20 and acquiring, for example, information of a higher
layer from the received signals. The transmitting unit 110 has a
function of transmitting the NR-PSS, the NR-SSS, the NR-PBCH, the
DL/UL control signal, the DL reference signal, or the like to the
user equipment 20.
[0088] The setting unit 130 stores pre-configured configuration
information and various types of configuration information to be
transmitted to the user equipment 20 in the storage device and
reads the configuration information from the storage device if
necessary. For example, content of the configuration information
is, for example, information related to a resource configuration of
the D2D communication or the like.
[0089] As described in the embodiment, the control unit 140
performs a process related to the resource configuration used for
the user equipment 20 to perform the D2D communication. The control
unit 140 transmits the scheduling of the D2D communication to the
user equipment 20 via the transmitting unit 110. A functional unit
related to signal transmission in the control unit 140 may be
included in the transmitting unit 110, and a functional unit
related to signal reception in the control unit 140 may be included
in the receiving unit 120.
User Equipment 20
[0090] FIG. 17 is a diagram illustrating an example of a functional
configuration of the user equipment 20. As illustrated in FIG. 17,
the user equipment 20 has a transmitting unit 210, a receiving unit
220, a setting unit 230, and a control unit 240. The functional
configuration illustrated in FIG. 17 is merely an example. As long
as the operation according to an embodiment of the present
invention can be executed, the function classification and the name
of the function unit are not consequential.
[0091] The transmitting unit 210 generates a transmission signal
from transmission data and transmits the transmission signal
wirelessly. The receiving unit 220 wirelessly receives various
types of signals, and acquires a signal of a higher layer from a
received signal of a physical layer. The receiving unit 220 also
has a function of receiving the NR-PSS, the NR-SSS, the NR-PBCH,
the DL/UL/SL control signal, the reference signal, or the like
transmitted from the base station device 10. Further, for example,
the transmitting unit 210 may transmit a physical sidelink control
channel (PSCCH), a physical sidelink shared channel (PSSCH), a
physical sidelink discovery channel (PSDCH), a physical sidelink
broadcast channel (PSBCH), and the like to other units of user
equipment 20 as the D2D communication, and the receiving unit 220
receives the PSCCH, the PSSCH, the PSDCH, the PSBCH, and the like
from other units of user equipment 20.
[0092] The setting unit 230 stores various types of configuration
information received from the base station device 10 or the user
equipment 20 through the receiving unit 220 in the storage device
and reads the configuration information from the storage device if
necessary. The setting unit 230 also stores pre-configured
configuration information. For example, content of the
configuration information is, for example, information related to
the configuration of the D2D communication or the like.
[0093] The control unit 240 controls the D2D communication with
other units of user equipment 20 as described in the embodiment.
Further, the control unit 240 executes the sensing and the
autonomous resource selection. Further, the control unit 240 may
execute the scheduling of the D2D communication. A functional unit
related to signal transmission in the control unit 240 may be
included in the transmitting unit 210, and a functional unit
related to signal reception in the control unit 240 may be included
in the receiving unit 220.
Hardware Configuration
[0094] In the block diagrams (FIGS. 16 and 17) used for the
description of the above embodiment, the blocks of the functional
units are illustrated. The functional blocks (configuring units)
are implemented by at least an arbitrary combination of hardware
and/or software. A method of implementing each functional block is
not particularly limited. In other words, each functional block may
be implemented by one device in which a plurality of elements are
physically and/or logically combined or may be implemented by a
plurality of devices, that is, two or more devices which are
physically and/or logically separated and are directly and/or
indirectly connected (for example, in a wired and/or wireless
manner or the like). The function block may be realized by
combining software with one device or a plurality of devices.
[0095] The functions include determining, deciding, judging,
computing, calculating, processing, deriving, investigating,
searching, confirming, receiving, transmitting, outputting,
accessing, resolving, selecting, choosing, establishing, comparing,
assuming, expecting, regarding, broadcasting, notifying,
communicating, forwarding, configuring, reconfiguring, allocating,
mapping, assigning, and the like but are not limited thereto. For
example, a functional block (configuring unit) that causes
transmission to function is referred to as a transmitting unit or a
transmitter. In any case, as described above, an implementation
method is not particularly limited.
[0096] For example, the base station device 10, the user equipment
20, or the like in one embodiment of the present disclosure may
function as a computer for processing the present disclosure's
wireless communication method. FIG. 18 is a diagram illustrating an
example of a hardware configuration of the base station device 10
and the user equipment 20 according to an embodiment of the present
disclosure. Each of the base station device 10 and the user
equipment 20 may be physically configured as a computer device
including a processor 1001, a storage device 1002, an auxiliary
storage device 1003, a communication device 1004, an input device
1005, an output device 1006, a bus 1007, and the like.
[0097] In the following description, the term "device" can be read
as a circuit, device, unit, or the like. The hardware configuration
of each of the base station device 10 and the user equipment 20 may
be configured to include one or more devices illustrated in the
drawing or may be configured without including some devices.
[0098] Each function in each of the base station device 10 and the
user equipment 20 is implemented such that predetermined software
(program) is read on hardware such as the processor 1001 and the
storage device 1002, and the processor 1001 performs an operation
and controls communication by the communication device 1004 and
reading and/or writing of data in the storage device 1002 and the
auxiliary storage device 1003.
[0099] For example, the processor 1001 operates an operating system
and controls the entire computer. The processor 1001 may be
configured with a central processing unit (CPU) including an
interface with a peripheral device, a control device, an operation
device, a register, and the like. For example, the control unit
140, the control unit 240, and the like described above may be
implemented by the processor 1001.
[0100] Further, the processor 1001 reads a program (program code),
a software module, or data from at least one of the auxiliary
storage device 1003 and/or the communication device 1004 out to the
storage device 1002, and executes various types of processes
according to them. A program causing a computer to execute at least
some of the operations described in the above embodiment is used as
the program. For example, the control unit 140 of the base station
device 10 illustrated in FIG. 16 may be implemented by a control
program which is stored in the storage device 1002 and operates on
the processor 1001. Further, for example, the control unit 240 of
the user equipment 20 illustrated in FIG. 17 may be implemented by
a control program which is stored in the storage device 1002 and
operates on the processor 1001. Various types of processes have
been described as being performed by one processor 1001 but may be
performed simultaneously or sequentially by two or more processors
1001. The processor 1001 may be implemented by one or more chips.
The program may be transmitted from a network via an electric
communication line.
[0101] The storage device 1002 is a computer readable recording
medium and configured with at least one of a read only memory
(ROM), an erasable programmable ROM (EPROM), an electrically
erasable programmable ROM (EEPROM), a random access memory (RAM),
and the like. The storage device 1002 is also referred to as a
"register" a "cache" a "main memory," or the like. The storage
device 1002 can store programs (program codes), software modules,
or the like which are executable for carrying out the communication
method according to an embodiment of the present disclosure.
[0102] The auxiliary storage device 1003 is a computer-readable
recording medium and may be configured with, for example, at least
one of an optical disk such as a compact disc ROM (CD-ROM), a hard
disk drive, a flexible disk, a magneto-optical disk (for example, a
compact disk, a digital versatile disk, or a Blu-ray (registered
trademark) disc, a smart card, a flash memory (for example, a card,
a stick, or a key drive), a floppy (registered trademark) disk, a
magnetic strip, and the like. The auxiliary storage device 1003 is
also referred to as an "auxiliary storage device." The storage
medium may be, for example, a database, a server, or any other
appropriate medium including at least one of the storage device
1002 and the auxiliary storage device 1003.
[0103] The communication device 1004 is hardware (a transceiving
device) for performing communication between computers via at least
one of a wired network and a wireless network and is also referred
to as a "network device," a "network controller," a "network card,"
a "communication module," or the like. The communication device
1004 may include a high-frequency switch, a duplexer, a filter, a
frequency synthesizer, or the like in order to implement at least
one of frequency division duplex (FDD) and time division duplex
(TDD). For example, a transceiving antenna, an amplifying unit, a
transmitting/receiving unit, a transmission line interface, or the
like may be implemented by the communication device 1004. The
transmitting/receiving unit may be implemented by to be physically
or logically separated by a transmitting unit and a receiving
unit.
[0104] The input device 1005 is an input device that receives an
input from the outside (such as a keyboard, a mouse, a microphone,
a switch, a button, a sensor, or the like). The output device 1006
is an output device that performs an output to the outside (for
example, a display, a speaker, an LED lamp, or the like). The input
device 1005 and the output device 1006 may be integratedly
configured (for example, a touch panel).
[0105] The respective devices such as the processor 1001 and the
storage device 1002 are connected via the bus 1007 to communicate
information with each other. The bus 1007 may be configured with a
single bus or may be configured with different buses between the
devices.
[0106] Further, each of the base station device 10 and the user
equipment 20 may be configured to include hardware such as a
microprocessor, a digital signal processor (DSP), an application
specific integrated circuit (ASIC), a programmable logic device
(PLD), or a field programmable gate array (FPGA) or all or some of
the functional blocks may be implemented by hardware. For example,
the processor 1001 may be implemented using at least one of these
pieces of hardware.
Conclusion of the Embodiments
[0107] As described above, according to an embodiment of the
present invention, provided is a user equipment that includes a
receiving unit that executes sensing for a part of candidate
resources to be used for transmission of inter-terminal direct
communication, a control unit that determines a resource to be used
for transmission based on a result of the sensing, and a
transmitting unit that transmits a message to other units of user
equipment using the determined resource.
[0108] With the above configuration, when the scheduling type MAC
such as the centralized MAC or the semi-distributed MAC coexists
with the autonomous resource selection type MAC such as the
distributed MAC, the user equipment 20 can improve the performance
of the system by preventing the collision of the SL resource. In
other words, it is possible to reduce the collision of the
resources used by the user equipment in the inter-terminal direct
communication.
[0109] The part of the candidate resources to be used for the
transmission may be one symbol at a beginning in a time domain of
the candidate resources to be used for the transmission or a
plurality of symbols allocated from a second symbol from the
beginning. With this configuration, the user equipment 20 can
detect early whether or not the resource is used by executing
sensing near the beginning of the resource.
[0110] When it is detected that a resource is used in the one
symbol at the beginning in the time domain of the candidate
resource to be used for the transmission, the plurality of symbols
allocated from the second symbol from the beginning may not be
sensed. With this configuration, the user equipment 20 can suppress
unnecessary sensing by performing sensing in one symbol at the
beginning of the resource.
[0111] When it is not detected that a resource is used in the one
symbol at the beginning in the time domain of the candidate
resource to be used for the transmission, the plurality of symbols
allocated from the second symbol from the beginning may be sensed.
With this configuration, the user equipment 20 can execute sensing
only if necessary by performing sensing in one symbol at the
beginning of the resource.
[0112] When a notification indicating that candidate resources to
be used for transmission are scheduled is given, the candidate
resources to be used for the transmission may not be sensed and may
be excluded from resource candidates used for transmission. With
this configuration, the user equipment 20 can suppress unnecessary
sensing by being notified that the resource is scheduled.
[0113] According to an embodiment of the present invention,
provided is a base station device including a receiving unit that
receives information indicating that a candidate resource used for
transmission of inter-terminal direct communication is reserved by
a first user equipment and a control unit that prevents scheduling
the candidate resources to be used for the transmission to a user
equipment based on the information indicating the reservation, in
which, when the candidate resource to be used for the transmission
is already scheduled to a second user equipment, scheduling a new
resource to the first user equipment is executed.
[0114] With the above configuration, when the scheduling type MAC
such as the centralized MAC or the semi-distributed MAC coexists
with the autonomous resource selection type MAC such as the
distributed MAC, the user equipment 20 can improve the performance
of the system by preventing the collision of the SL resource. In
other words, it is possible to reduce the collision of the
resources used by the user equipment in the inter-terminal direct
communication.
Supplement of Embodiment
[0115] The exemplary embodiment of the present invention has been
described above, but the disclosed invention is not limited to the
above embodiments, and those skilled in the art would understand
various modified examples, revised examples, alternative examples,
substitution examples, and the like. In order to facilitate
understanding of the invention, specific numerical value examples
have been used for description, but the numerical values are merely
examples, and certain suitable values may be used unless otherwise
stated. The classification of items in the above description is not
essential to the present invention. Matters described in two or
more items may be combined and used if necessary, and a matter
described in one item may be applied to a matter described in
another item (unless inconsistent). The boundary between functional
units or processing units in a functional block diagram does not
necessarily correspond to the boundary between physical parts.
Operations of a plurality of functional units may be performed
physically by one component, or an operation of one functional unit
may be physically performed by a plurality of parts. In the
processing procedure described in the embodiments, the order of the
processes may be changed as long as there is no inconsistency. For
the sake of convenience of processing description, the base station
device 10 and the user equipment 20 have been described using the
functional block diagrams, but such devices may be implemented by
hardware, software, or a combination thereof. Software executed by
the processor included in the base station device 10 according to
the embodiment of the present invention and software executed by
the processor included in the user equipment 20 according to the
embodiment of the present invention may be stored in a random
access memory (RAM), a flash memory, a read only memory (ROM), an
EPROM, an EEPROM, a register, a hard disk (HDD), a removable disk,
a CD-ROM, a database, a server, or any other appropriate storage
medium.
[0116] Further, a notification of information is not limited to the
aspect or embodiment described in the present disclosure and may be
given by any other method. For example, the notification of
information may be given by physical layer signaling (for example,
downlink control information (DCI) or uplink control information
(UCI)), upper layer signaling (for example, radio resource control
(RRC) signaling, medium access control (MAC) signaling, broadcast
information (master information block (MIB), system information
block (SIB)), other signals, or a combination thereof. Further, the
RRC signaling may be referred to as an RRC message and may be, for
example, an RRC connection setup message, an RRC connection
reconfiguration message, or the like.
[0117] Each aspect and embodiment of the present invention may be
applied to at least one of Long Term Evolution (LTE), LTE-advanced
(LTE-A), SUPER 3G, IMT-advanced, 4th generation mobile
communication system (4G), 5th generation mobile communication
system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA
(registered trademark), GSM (registered trademark), CDMA 2000,
Ultra Mobile Broadband (UMB), IEEE 902.11 (Wi-Fi (registered
trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE
802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), a
system using any other appropriate system, and next generation
systems extended based on these standards. Further, a plurality of
systems may be combined and applied (for example, a combination of
at least one of LTE and LTE-A and 5G or the like).
[0118] The processing procedures, the sequences, the flowcharts,
and the like of the respective aspects/embodiments described in
this specification may be reversed in order unless there is a
contradiction. For example, the method described in the present
disclosure presents elements of various steps using an exemplary
order and is not limited to a presented specific order.
[0119] In this specification, a specific action that is supposed to
be performed by the base station device 10 may be performed by an
upper node in some cases. In the network including one or more
network nodes including the base station device 10, various
operations performed for communication with the user equipment 20
can be obviously performed by at least one of the base station and
any network node (for example, an MME, an S-GW, or the like is
considered, but it is not limited thereto) other than the base
station device 10 and/or the base station device 10. The example in
which the number of network nodes excluding the base station device
10 is one has been described above, but other network nodes in
which a plurality of other network nodes (for example, an MME and
an S-GW) are combined may be provided.
[0120] Information, a signal, or the like described in the present
disclosure may be output from an upper layer (or a lower layer) to
a lower layer (or an upper layer). Information, a signal, or the
like described in the present disclosure may be input and output
via a plurality of network nodes.
[0121] Input and output information and the like may be stored in a
specific place (for example, a memory) or may be managed through a
management table. Input and output information and the like may be
overwritten, updated, or additionally written. Output information
and the like may be deleted. Input information and the like may be
transmitted to another device.
[0122] The determination the present disclosure may be performed in
accordance with a value (0 or 1) indicated by one bit, may be
performed in accordance with a Boolean value (true or false), or
may be performed by a comparison of numerical values (for example,
a comparison with a predetermined value).
[0123] Software can be interpreted widely to mean a command/ a
command set, a code, a code segment, a program code, a program, a
subprogram, a software module, an application, a software
application, a software package, a routine, a subroutine, an
object, an executable file, an execution thread, a procedure, a
function, and the like regardless of whether software is called
software, firmware middleware, a microcode, a hardware description
language, or any other name.
[0124] Further, software, commands, information, and the like may
be transmitted and received via a transmission medium. For example,
when software is transmitted from a web site, a server, or any
other remote source using a wired technology (such as a coaxial
cable, a fiber optic cable, a twisted pair, or a digital subscriber
line (DSL)) and a radio technology (such as infrared rays or a
microwave), at least one of the wired technology and the radio
technology are included in a definition of a transmission
medium.
[0125] Information, signals, and the like described in this
specification may be indicated using any one of a variety of
different techniques. For example, data, instructions, commands,
information, signals, bits, symbols chips, and the like which are
mentioned throughout the above description may be indicated by
voltages, currents, electromagnetic waves, magnetic particles,
optical fields or photons, or an arbitrary combination thereof.
[0126] The terms described in the present disclosure and terms
necessary for understanding the present disclosure may be replaced
with terms having the same or similar meanings. For example, at
least one of a channel and a symbol may be a signal. Further, a
signal may be a message. Further, a component carrier (CC) may be
referred to as a "carrier frequency," a "cell," or the like.
[0127] The terms "system" and "network" used in the present
disclosure are used interchangeably.
[0128] Further, information, parameters, and the like described in
the present disclosure may be indicated by absolute values, may be
indicated by relative values from predetermined values, or may be
indicated by corresponding other information. For example, radio
resources may be those indicated by an index.
[0129] The names used for the above-described parameters are not
limited in any respect. Further, mathematical formulas or the like
using the parameters may be different from those explicitly
disclosed in the present disclosure. Since various channels (for
example, a PUCCH, a PDCCH, and the like) and information elements
can be identified by suitable names, various names allocated to the
various channels and the information elements are not limited in
any respect.
[0130] In the present disclosure, the terms "base station (BS),"
"radio base station," "base station device," "fixed station," "Node
B," "eNode B (eNB)," "gNodeB (gNB)," "access point," "transmission
point," "reception point," "transmission/reception point," "cell,"
"sector," "cell group," "carrier," "component carrier," and the
like can be used interchangeably. The base stations may also be
indicated by terms such as a macrocell, a small cell, a femtocell,
and a picocell.
[0131] The base station eNB can accommodate one or more (for
example, three) cells. In a case in which the base station
accommodates a plurality of cells, the entire coverage area of the
base station can be partitioned into a plurality of small areas,
and each small area can provide a communication service through a
base station subsystem (for example, a small indoor base station (a
remote radio head (RRH)). The term "cell" or "sector" refers to the
whole or a part of the coverage area of at least one of the base
station and the base station subsystem that performs a
communication service in the coverage.
[0132] In the present disclosure, the terms "mobile station (MS),"
"user terminal," "user equipment (UE)," "terminal," and the like
can be used interchangeably.
[0133] The mobile station may be a subscriber station, a mobile
unit, a subscriber unit, a wireless unit, a remote unit, a mobile
device, a wireless device, a wireless communication device, a
remote device, a mobile subscriber station, an access terminal, a
mobile terminal, a wireless terminal, it may also be referred to as
a remote terminal, handset, user agent, mobile client, client, or
some other suitable term.
[0134] At least one of the base station and the mobile station may
be also referred to as a transmitting device, a receiving device, a
communication device, or the like. At least one of the base station
and the mobile station may be a device installed in a mobile body,
a mobile body itself, or the like. The moving body may be a vehicle
(for example, a car, an airplane, or the like), a moving body that
moves unmanned (for example, a drone, an autonomous car or the
like), or a robot (manned type or unmanned type). At least one of
the base station and the mobile station includes a device which
need not necessarily move during a communication operation. For
example, at least one of the base station and the mobile station
may be an Internet of things (IoT) device such as a sensor.
[0135] Further, the base station in the present disclosure may be
replaced with a user terminal. For example, each aspect/embodiment
of the present disclosure may be applied to a configuration in
which communication between the base station and the user terminal
is replaced with communication between a plurality of units of user
equipment 20 (for example/ which may be referred to as
device-to-device (D2D) or vehicle-to-everything (V2X)). In this
case, the user equipment 20 may have the functions of the base
station described above. Further, the terms "uplink" and "downlink"
may be replaced with terms (for example, "side") corresponding to
inter-terminal communication. For example, an uplink channel, a
downlink channel, or the like may be read with side channels.
[0136] Similarly, the user terminal in the present disclosure may
be replaced with the base station. In this case, the base station
may have the functions of the above-mentioned user terminal.
[0137] The term "determining" used in this specification may
include a wide variety of actions. For example, "determining" may
include, for example, events in which events such as judging,
calculating, computing, processing, deriving, investigating,
looking up, search, and inquiry (for example, looking up in a
table, a database, or another data structure), or ascertaining are
regarded as "determining." Further, "determining" may include, for
example, events in which events such as receiving (for example,
receiving information), transmitting (for example, transmitting
information), input, output, or accessing (for example, accessing
data in a memory) are regarded as "determining." Further,
"determining" may include, for example, events in which events such
as resolving, selecting, choosing, establishing, or comparing are
regarded as "determining." In other words, "determining" may
include events in which a certain operation is regarded as
"determining" or "deciding." Further, "determining" may be replaced
with "assuming," "expecting," "considering," or the like.
[0138] Terms "connected," "coupled," or variations thereof means
any direct or indirect connection or coupling between two or more
elements and may include the presence of one or more intermediate
elements between two elements which are "connected" or "coupled."
The coupling or the connection between the elements may be
physical, logical, or a combination thereof. For example,
"connection" may be replaced with "access." In a case in which used
in the present disclosure, two elements may be considered to be
"connected" or "coupled" with each other using at least one of one
or more electric wires, cables and/or a printed electrical
connection or using electromagnetic energy having a wavelength in a
radio frequency domain, a microwave region, or a light (both
visible and invisible) region as non-limiting and non-exhaustive
examples.
[0139] A reference signal may be abbreviated as RS and may be
referred to as a pilot, depending on a standard to be applied.
[0140] A phrase "based on" used in the present disclosure is not
limited to "based on only" unless otherwise stated. In other words,
a phrase "based on" means both "based on only" and "based on at
least."
[0141] Any reference to an element using a designation such as
"first," "second," or the like used in the present disclosure does
not generally restrict quantities or an order of those elements.
Such designations can be used in the present disclosure as a
convenient method of distinguishing two or more elements. Thus,
reference to the first and second elements does not mean that only
two elements can be adopted there, or the first element must
precede the second element in a certain form.
[0142] Further, "means" in the configuration of each of the above
devices may be replaced with "unit," "circuit," "device," or the
like.
[0143] In a case in which "include," "including," and variations
thereof are used in the present disclosure, these terms are
intended to be comprehensive, similarly to a term "equipped with
(comprising)." Further, the term "or" used in the present
disclosure is intended not to be an exclusive disjunction.
[0144] A radio frame may include one or more frames in the time
domain. In the time domain, each of one or more frames may be
referred to as a sub frame. The sub frame may further include one
or more slots in the time domain. The sub frame may have a fixed
time length (for example, 1 ms) not depending on numerology.
[0145] The numerology may be a communication parameter applied to
at least one of transmission and reception of a certain signal or
channel. For example, the numerology may indicate at least one of a
sub carrier spacing (SCS), a bandwidth, a symbol length, a cyclic
prefix length, a transmission time interval (TTI), a number of
symbols per TTI, a radio frame configuration, a specific filtering
process performed in the frequency domain by a transceiver, a
specific windowing process performed in the time domain by a
transceiver, and the like.
[0146] The slot may include one or more symbols (orthogonal
frequency division multiplexing (OFDM) symbols, single carrier
frequency division multiple access (SC-FDMA) symbols, or the like)
in the time domain. The slot may be a time unit based on the
numerology.
[0147] The slot may include a plurality of mini slots. Each mini
slot may include one or more symbols in the time domain. Further,
the mini slot may be referred to as a sub-slot. The mini slot may
include fewer symbols than a slot. A PDSCH (or PUSCH) transmitted
in units of times greater than the mini slot may be referred to as
a PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted
using a mini slot may be referred to as a PDSCH (or PUSCH) mapping
type B.
[0148] All of a radio frame, a sub frame, a slot, a mini slot, and
a symbol indicates a time unit for transmitting a signal. As a
radio frame, a sub frame, a slot, a mini slot, and a symbol,
different designations respectively corresponding to them may be
used.
[0149] For example, one sub frame may be referred to as a
transmission time interval (TTI: Transmission Time Interval), or a
plurality of consecutive sub frames may be referred to as TTIs, or
one slot or one mini slot may be referred to as a TTI. In other
words, at least one of the sub frame and the TTI may be a sub frame
(1 ms) in the existing LTE, may be a period shorter than 1 ms (for
example, 1 to 13 symbols), or may be referred to as a period longer
than 1 ms. A unit representing the TTI may be referred to as slot,
a mini slot, or the like instead of the sub frame.
[0150] Here, for example, the TTI refers to a minimum time unit of
scheduling in wireless communication. For example, in the LTE
system, the base station performs scheduling of allocating a radio
resource (a frequency bandwidth, a transmission power, or the like
which can be used in each user equipment 20) to each user equipment
20 in units of TTIs. The definition of the TTI is not limited
thereto.
[0151] The TTI may be a transmission time unit such as a channel
coded data packet (transport block), a code block, or a code word,
or may be a processing unit such as scheduling or link adaptation.
Further, when a TTI is given, a time interval (for example, the
number of symbols) in which a transport block, a code block, a code
word, or the like is actually mapped may be shorter than the
TTI.
[0152] Further, when one slot or one mini slot is referred to as a
TTI, one or more TTIs (that is, one or more slots or one or more
mini slots) may be a minimum time unit of scheduling. Further, the
number of slots (the number of mini slots) constituting the minimum
time unit of scheduling may be controlled.
[0153] A TTI having a time length of 1 ms may be referred to as a
common TTI (TTI in LTE Rel. 8 to 12), a normal TTI, a long TTI, a
common sub frame, a normal sub frame, a long sub frame, a slot, or
the like. A TTI shorter than the common TTI may be referred to as a
reduced TTI, a short TTI, a partial TTI (a partial or fractional
TTI), a reduced sub frame, a short sub frame, a mini slot, a sub
slot, a slot, or the like.
[0154] Further, a long TTI (for example, a common TTI, a sub frame,
or the like) may be replaced with a TTI having a time length
exceeding 1 ms, and a short TTI (for example, a reduced TTI or the
like) may be replaced with a TTI having a TTI length which is less
than a TTI length of a long TTI and equal to or more than 1 ms.
[0155] The resource block (RB) is a resource allocation unit in the
time domain and the frequency domain and may include one or more
consecutive subcarriers in the frequency domain. The number of sub
carriers included in an RB may be the same irrespective of a
numerology and may be, for example, 12. The number of sub carriers
included in an RB may be determined based on a numerology.
[0156] Further, a time domain of an RB may include one or more
symbols and may be a length of one slot, one mini slot, one sub
frame, or one TTI. Each of one TTI, one sub frame, or the like may
be constituted by one or more resource blocks.
[0157] Further, one or more RBs may be referred to as a physical
resource block (PRB), a sub carrier group (SCG), a resource element
group (REG), a PRB pair, a RB pair, or the like.
[0158] Further, the resource block may be constituted by one or
more resource elements (RE). For example, one RE may be a radio
resource region of one subcarrier and one symbol.
[0159] A bandwidth part (BWP) (which may be referred to as a
partial bandwidth) may indicate a subset of consecutive common
resource blocks (RBs) for a certain numerology in a certain
carrier. Here, a common RB may be specified by an index of an RB
based on a common reference point of a carrier. A PRB may be
defined in a BWP and numbered in a BWP.
[0160] The BWP may include a BWP for UL (UL BWP) and a BWP for DL
(DL BWP). In a UE, one or more BWPs may be configured within one
carrier.
[0161] At least one of configured BWPs may be active, and it may
not be assumed that the UE transmits and receives a predetermined
signal/channel outside an active BWP. Further, a "cell," a
"carrier," or the like in the present disclosure may be replaced
with a "BWP."
[0162] Structures of the radio frame, the sub frame, slot, the mini
slot, and the symbol are merely examples. For example,
configurations such as the number of sub frames included in a radio
frame, the number of slots per sub frame or radio frame, the number
of mini slots included in a slot, the number of symbols and RBs
included in a slot or a mini slot, the number of sub carriers
included in an RB, the number of symbols in a TTI, a symbol length,
a cyclic prefix (CP) length, and the like can be variously
changed.
[0163] In the entire present disclosure, for example, when an
article such as "a," "an," or "the" in English is added by a
translation, the present disclosure may include a case in which a
noun following the article is the plural.
[0164] In the present disclosure, a term "A and B are different"
may mean "A and B are different from each other." Further, the term
may mean "each of A and B is different from C." Terms such as
"separated," "coupled," or the like may also be interpreted in
similarly to "different."
[0165] Each aspect/embodiment described in this specification may
be used alone, in combination, or may be switched in accordance
with the execution. Further, notification of predetermined
information (for example, notification of "being X") is not limited
to being performed explicitly, but is performed by implicit (for
example, not notifying the predetermined information) It is also
good.
[0166] Although the present disclosure has been described above in
detail, it is obvious to those skilled in the art that the present
disclosure is not limited to the embodiments described in the
present disclosure. The present disclosure may be implemented as
revised and modified forms without departing from the gist and
scope of the present disclosure as configured forth in claims.
Therefore, the description of the present disclosure is for the
purpose of illustration and does not have any restrictive meaning
to the present disclosure.
LIST OF REFERENCE SYMBOLS
[0167] 10 BASE STATION DEVICE
[0168] 110 TRANSMITTING UNIT
[0169] 120 RECEIVING UNIT
[0170] 130 SETTING UNIT
[0171] 140 CONTROL UNIT
[0172] 20 USER EQUIPMENT
[0173] 210 TRANSMITTING UNIT
[0174] 220 RECEIVING UNIT
[0175] 230 SETTING UNIT
[0176] 240 CONTROL UNIT
[0177] 1001 PROCESSOR
[0178] 1002 STORAGE DEVICE
[0179] 1003 AUXILIARY STORAGE DEVICE
[0180] 1004 COMMUNICATION DEVICE
[0181] 1005 INPUT DEVICE
[0182] 1006 OUTPUT DEVICE
* * * * *